title: Ketamine antagonizes toxic action of anticholinesterase agents.
abstract: Ketamine is an anaesthetic interacting with several neurotransmitters. Among others, ketamine exerts some cholinergic actions (ACh). This paper presents the results of studying the interaction of ketamine with ACh in two animal species. Atropine slightly increased the time of immobility produced by ketamine injections in rats. Meanwhile, neostigmine slightly decreased such immobility. Ketamine resulted similar in behavioral actions and shared some electroencephalographic (EEG) actions of scopolamine in cats. The most striking interaction consisted on an antagonism of ketamine on the action of anticholinesterase agents. In both species, ketamine blocked the EEG and the behavioral toxic effects of neostigmine and physostigmine. Notwithstanding, the anticholinesterase agents were unable in reducing the actions of ketamine. This partial cholinergic agonist action of ketamine support certain but limited use of the anesthetic against insecticidal anticholinesterase poisoning.
authors.affiliation: Departamento de Fisiología, Instituto de Investigaciones Biomédicas, U.N.A.M., Universidad Veracruzana, México.
authors.forename: C M
authors.initials: CM
authors.lastname: Contreras
authors.forename: M L
authors.initials: ML
authors.lastname: Marvan
authors.forename: G
authors.initials: G
authors.lastname: Mexicano
authors.forename: A
authors.initials: A
authors.lastname: Puente
authors.forename: A
authors.initials: A
authors.lastname: Morfin
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D002415:Cats; D002800:Cholinesterase Inhibitors / Q000494:pharmacology* / Q000633:toxicity; D004347:Drug Interactions; D004569:Electroencephalography / Q000187:drug effects; D005260:Female; D007649:Ketamine / Q000494:pharmacology*; D008297:Male; D009388:Neostigmine / Q000037:antagonists & inhibitors / Q000633:toxicity; D010830:Physostigmine / Q000037:antagonists & inhibitors / Q000633:toxicity; D051381:Rats; D011919:Rats, Inbred Strains; D011976:Receptors, Muscarinic / Q000187:drug effects; D013045:Species Specificity
chemical_list: D002800:Cholinesterase Inhibitors; D011976:Receptors, Muscarinic; D009388:Neostigmine; D007649:Ketamine; D010830:Physostigmine